anti-hijack

Hi. I'm trying to make an anti-hijack system for a diesel van. Needs to hold power to the fuel pump solenoid when the keys are removed from the ignition so vehicle battery will remain charging, but don't want anyone to be able to drive off!!

I know some systems are available, but there must be a cheaper way! I've taken a couple of circuits and combined / modified them, would just really appreciate anyone looking over my plan and giving any suggestions. Or pointing out any faults!

Vehicle will be left WITHOUT keys in, and if i've done it right, will cut out (with no restart capability) if clutch or brake pressed  or  handbrake released.

One last thing. I know it may not be legal, or insurance approved, but hey, needs must.

Thanks.

Thanks for the input, and yes, i realise it could be done easier. But i'm trying to utilise the momentary switch and L.E.D. that were fitted to the dash previously and are now redundant, save drilling more holes. I appreciate that would get rid of the need for 4 relays!

Its on a breakdown recovery vehicle, which needs to be left unattended sometimes but running to keep all the lights and warnings going, but some other firms locally have had their vehicles stolen, hence the over-kill.

Again, thanks for time to help.